JPH01151529A - Production of carboxylic chloride - Google Patents

Abstract

A new process for the preparation of carboxylic acid chlorides by reaction of tetrachloroethylene carbonate with a carboxylic acid of formula R(COOH)n at a temperature of between 80 DEG and 160 DEG C. <??>The radical R can be very varied and n is an integer which can asssume the values 1 to 4. <??>A solvent is not necessary. A catalyst may be employed. <??>The acid chlorides are obtained in a high purity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field] The present invention relates to a new process for producing chlorides of carboxylic acids from the corresponding carboxylic acids.

[Prior Art] Various methods have been proposed for producing carboxylic acid chlorides from carboxylic acids ("Methoden de
"Organischen Chemie", tlo
(see page uben-WeyL Vo j2 L 4O4).

That is, phosphorus pentachloride can be used.

R-COOII + PC! ! , s→R−C−Cf +
I'OCf 3+ IIc j2 However, phosphorus pentachloride is a solid and sensitive to hydrolysis and is therefore not very convenient to use.

Phosphorus trichloride can be used.

3R-COOH+ PCe :l →3R-C-Cf
+113Po.

o Phosphorus trichloride requires large excesses on the order of 25-100%, and yields are highly variable due to the many secondary reactions [The chemistry of Acy
111alides', 5aul Patai, Tn
tersciences Publishers-Wi
ley & 5ons (1972) pp. 40-41]
.

Thionyl chloride can be used.

R-COOII + SOC1z→R-C-Cf +
When using HCf + SO□thionyl chloride, the addition of a catalyst is generally necessary (tl, M, Bosch
ard et al., l1elv, chem.

Acta (1959) 62.1633).

Oxalyl chloride can be used.

Oxalyl chloride is highly toxic and expensive (N,
0. V, Sonntag et al., J, H.
Oil Chemist Soc.

(1954) -3L 151) Phosgene can be used.

R-COOfl +COC42z→R-C-Cl +I
ICl + COz However, in the absence of a catalyst the reaction must be carried out at high temperature and pressure (US Patent N.
o.

2.657,233). In addition, this stuff is a toxic substance and its transportation is dangerous, so a very special plant is required near its production site.

[Problem to be solved by the invention]

It can be seen that the use of various methods of the prior art always brings disadvantages. Acyl chlorides are obtained with interfering by-products or the reaction is difficult to carry out due to toxicity problems.

It is therefore of great importance to develop new processes for the production of chlorides of carboxylic acids, which do not require the use of hazardous substances and which can obtain acyl chlorides of high purity.

The present invention satisfies the above expectations and is directed to a process for preparing acyl chlorides using reactants that are less toxic and do not produce impurities.

[Means to solve the problem]

The method of the present invention is a method for producing a chloride of a carboxylic acid by reacting tetrachloroethylene carbonate with the corresponding carboxylic acid at a temperature of 80°C to 160°C.

[Specific explanation]

The reaction method is as follows.

Tetrachloroethylene carbonate used to carry out the process of the invention is a known compound. It can be easily prepared by photochemical reaction of chlorine and ethylene carbonate, as described in US Pat. No. 2,816,287.

The carboxylic acids used in the reaction vary widely.

These are commercially available or can be manufactured according to known methods.

Addition of catalyst is unnecessary.

It can be used if a solvent is really needed, for example when the acyl chloride has a low boiling point or when the acid has a high melting point.

The acyl chloride obtained is very pure and free of interfering products.

Implementation of this method is simple. No distillation is necessary to recover the acyl chloride, and this advantage is particularly valuable in the production of unstable acyl chlorides or acyl chlorides with high boiling points.

The present invention will be explained in further detail.

The method of the invention applies in particular to carboxylic acids of the formula R(COOR), where R is linear or branched C1-
C30 alkyl group [this group may contain one or more double or triple carbon-carbon bonds and includes a halogen atom, an aryl group, an aryloxy group, an alkoxy group, an alkyloxycarbonyl group, an aryloxycarbonyl group and one or more substituents selected from 5- or 6-membered heterocyclic groups, where the group is saturated or unsaturated and the heteroatom is selected from sulfur or oxygen atoms. -〇3~Ct cycloalkyl group (this group can contain one or more carbon-carbon double bonds if it contains 5 to 7 carbon atoms, and This group is a halogen atom, an alkyl group,
(can carry one or more substituents selected from alkenyl, aryl, alkyloxycarbonyl and aryloxycarbonyl groups); fused or non-fused aromatic or heteroaromatic groups [ In this group the heteroatom is selected from a sulfur atom, an oxygen atom or a nitrogen atom, the group being a halogen atom, an alkyl or haloalkyl group (containing one or more double or triple bonds or not), may carry one or more substituents selected from an aryl group, an alkoxy group, an aryloxy group, an alkyloxycarbonyl group, an aryloxycarbonyl group, a nitro group and a cyano group; or 5- -membered or 6-membered non-aromatic heterocyclic groups (containing one or more heteroatoms selected from atoms and sulfur, may contain one or more double bonds, and alkyl substituted or unsubstituted by one or more of the following groups: alkyloxycarbonyl and aryloxycarbonyl;
And n is an integer from 1 to 4.

More particularly, R is a straight-chain or branched C9-C2 alkyl group, which may contain one or more double or triple carbon-carbon bonds, and a chlorine atom, a bromine atom, , fluorine atom, C, -C4 alkoxy group, phenyl group, naphthyl group, phenoxy group, naphthoxy group, C3~
1 selected from C4 alkoxycarbonyl group, phenoxycarbonyl group, furyl group, pyranyl group and thienyl group
(can contain one or more substituents), C4
1-Cb cycloalkyl group (this group can contain one double bond if it contains 5-6 carbon atoms, and this group can contain 01-C, alkyl and alkenyl groups) ), or aromatic or heteroaromatic groups in which the heteroatoms are selected from sulfur, oxygen and nitrogen atoms, fused or non-condensed. 5-membered or 6-membered condensation
a halogen atom, a 01-C1□alkyl group, a fluoro- or chloro-alkyl group with or without one or more double or triple bonds, a 06-C3° aryl group containing a membered heterocycle; ,C1
~C+Z can carry one or more substituents selected from alkoxy group, C5-C6-C10 aryloxy group, 01-C4 alkoxycarbonyl group, phenoxycarbonyl group, nitro5 and cyano group). and in particular phenyl, naphthyl, furyl, benzofuryl, phenoxy or naphthoxy; and n has a value of 1 or 2.

Examples of acids that can be used within the scope of the invention include:
Propionic acid, butyric acid, isobutyric acid, valeric acid, isocrotonic acid, piparic acid, hexanoic acid, octanoic acid, decanoic acid, lauric acid, palmitic acid, stearic acid, tricontanonic acid, undecylenic acid, acrylic acid, methacrylic acid, crotonic acid, isocrotonic acid, propargyl acid,
Vinyl acetic acid, oleic acid, chloroacetic acid, dichloroacetic acid,
Trichloroacetic acid, bromoacetic acid, dibromoacetic acid, tribromoacetic acid, α-chloropropionic acid, α-chlorobutyric acid, malonic acid, succinic acid, adipic acid, sebacic acid, monomethyl ester of malonic acid, monomethyl ester of succinic acid, phenylacetic acid, Phenyloxyacetic acid, β-phenylpropionic acid, β-phenyloxypropionic acid, cyclopropanecarboxylic acid, 2,2-dimethyl-3-(2-methylpropenyl)cyclopropanecarboxylic acid, cyclohexanecarboxylic acid, 1,4-cyclohexane Dicarboxylic acid, cyclohexenecarboxylic acid, 2-thienyl-4-butyric acid, methoxyacetic acid, tiglic acid, angelic acid, fumaric acid, maleic acid, brassylic acid, benzoic acid, toluic acid,
halobenzoic acid, mononitrobenzoic acid, cyanobenzoic acid,
Isophthalic acid, terephthalic acid, 3-phenoxybenzoic acid, 4-tetrabutylbenzoic acid, furoic acid
acid), benzofuroic acid
c acid), thenoic acid
), nicotinic acid, isonicotinic acid, quinoline carboxylic acid, indole carboxylic acid, biphenyl carboxylic acid, 3,
Examples include, but are not limited to, 4.5-methoxybenzoic acid, 4-methoxycarbonylbenzoic acid, trifluoromethylbenzoic acid, and napucrenecarboxylic acid.

Tetrachloroethylene carbonate is preferably added progressively to the reaction medium, which has been preheated and maintained at the selected temperature. It is generally used in an amount of 0.50 to 0.75 equivalents, and preferably 0.52 to 0.6 equivalents, relative to the acid groups to be converted.

If possible, it is preferable to carry out the reaction without using a solvent. If it is desired to produce a low-boiling acyl chloride, or if the corresponding acid has a high melting point, e.g. Solvents can be used, such as one or more inert solvents selected from toluene, xylene, chlorobenzene and dichloroenzene.

Although a catalyst is not absolutely necessary to carry out the reaction, the addition of a catalytic compound makes it possible to shorten the reaction time and lower the temperature.

This catalyst is selected among catalysts already known and used in reactions for the production of chlorides of carboxylic acids.

These are selected in particular from the following group:

Φ Tertiary amines and their hydrochlorides, especially pyridine and 4-N,N-dimethylpyridine (DM8); Φ Quaternary ammonium salts, and especially chlorides and bromides, such as tetra-n-butyl quaternary ammonium salts and quaternary ammonium salts of benzyltri-n-butyl; ■Quaternary phosphonium salts; ON, N-disubstituted amide necks, especially N, N-dimethylformamide, and their combination with pc13. P(,es.

POCe: l, COCl z, SOCl□, or (
Co) zCl g(Vilsmeier-11aa
reaction products with compounds such as e.g.

POCl 3. COCE□, 5OCfz or (CO)
reaction products with compounds such as zC422; ■ hexaalkylphosphoramides, such as hexamethylphosphorotriamide (HMPT); ie hexaalkylguanidinium salts, especially the chlorides; and EP Application No. 2
their hydrochloride salts as described in 13,976;
Particularly hexamethylguanidinium chloride and hexabutylguanidinium chloride.

The amount of catalyst added is generally 1% per acid group to be converted.
0-4 to 10-I equivalent.

The temperature of chlorination is 80°C to 160°C. In the absence of a catalyst, the reaction is generally carried out at a temperature of 110°C to 160°C, and preferably 120°C to 160°C. If a catalyst is used, the reaction is generally carried out at 80°C-150°C.
1°C and preferably at 100°C to 135°C.

The reaction time is generally 1 to 4 hours.

The process of the invention provides in a simple manner, from relatively inexpensive and non-toxic materials, highly pure acyl chlorides which can be used without further purification.

Acyl chloride is a well-known compound and its uses are diverse. They are used, for example, as synthetic intermediates for the production of esters, amides, peresters, peroxides, polymeric compounds, insecticidal and pharmaceutical products, and in the paper industry.

Next, the present invention will be explained in more detail with reference to examples, but the scope of the present invention is not limited thereby.

The carboxylic acid, solvent if appropriate, and catalyst are introduced into a reactor equipped with a stirrer, thermometer and reflux condenser. The reaction mixture is heated to the indicated temperature and, while maintaining this temperature, 0.0% for the acid groups to be converted.
50 to 0.6 equivalents of tetrachloroethylene carbonate)
(TCBC) will be introduced. At the end of the reaction (monitored by IR or PC), the acyl chloride is optionally separated from the remaining tetrachloroethylene carbonate by distillation.

The operating conditions and results are summarized in the table below.

Claims (1)

[Claims] 1. A method for producing a chloride of a carboxylic acid, which comprises reacting tetrachloroethylene carbonate with a carboxylic acid at a temperature of 80°C to 160°C. 2. Process according to claim 1, characterized in that tetrachloroethylene carbonate is added progressively to the preheated reaction medium. 3. 0.50-0.7 relative to the amount of acid groups to be converted
3. Process according to claim 1 or 2, characterized in that tetrachloroethylene carbonate is added in an amount of 5 equivalents, preferably 0.52 to 0.6 equivalents. 4, the carboxylic acid is represented by the formula R(COOH)_n,
where R is a straight-chain or branched C_1-C_3_0 alkyl group [this group may contain one or more double or triple carbon-carbon bonds, and a halogen atom, an aryl group, an aryloxy alkoxy, alkyloxycarbonyl, aryloxycarbonyl, and 5- or 6-membered heterocyclic groups, where the group is saturated or unsaturated and the heteroatom is selected from sulfur or oxygen atoms. C_3-C_7 cycloalkyl group (this group can contain one or more carbon- may contain carbon double bonds, and this group carries one or more substituents selected from halogen atoms, alkyl groups, alkenyl groups, aryl groups, alkyloxycarbonyl groups and aryloxycarbonyl groups. ); fused or non-fused
Aromatic or heteroaromatic radicals [in which the heteroatoms are selected from sulfur, oxygen or nitrogen atoms, the radicals include halogen atoms, alkyl or haloalkyl radicals (containing one or more double or triple bonds) carrying one or more substituents selected from aryl group, alkoxy group, aryloxy group, alkyloxycarbonyl group, aryloxycarbonyl group, nitro group, and cyano group or a 5- or 6-membered non-aromatic heterocyclic group (containing one or more heteroatoms selected from oxygen and sulfur;
and n is 1~
4. A method according to any one of claims 1 to 3, characterized in that the number is an integer of 4. 5, R is a straight-chain or branched C_1-C_2_0 alkyl group (this group may contain one or more double or triple carbon-carbon bonds, and a chlorine atom, a bromine atom,
Fluorine atom, C_1-C_4 alkoxy group, phenyl group,
Naphthyl group, phenoxy group, naphthoxy group, C_1-C
_4 1 selected from alkoxycarbonyl group, phenoxycarbonyl group, furyl group, pyranyl group and thienyl group
(can contain one or more substituents), C_
3 to C_6 cycloalkyl group (this group can contain one double bond if it contains 5 to 6 carbon atoms, and this group can contain from C_1 to C_5 alkyl groups and alkenyl groups) or aromatic or heteroaromatic groups in which the heteroatoms are chosen from sulfur, oxygen and nitrogen atoms, fused or non-fused. 5-membered or 6-membered heterocycle, and a halogen atom, C_1~
C_1_2 alkyl group, fluoro- or chloro-alkyl group with or without one or more double or triple bonds, C_6 to C_1_
0 aryl group, C_1 to C_1_2 alkoxy group, C_
6 to C_1_0 aryloxy group, C_1 to C_4 alkoxycarbonyl group, phenoxycarbonyl group, nitro group and cyano group); and n is 1 or 2. 5. A method according to claim 4, characterized in that the value of . 6. Claims 1 to 6, characterized in that one or more solvents selected from chlorinated aliphatic solvents and aromatic solvents are used.
5. The method according to any one of 5. 7. As a catalyst, tertiary amines and their hydrochlorides; quaternary ammonium salts; quaternary phosphonium salts; N,N-
Disubstituted amides, and these and PCl_3, PCl_5
, POCl_3, COCl_2, SOCl_2 or (C
O) reaction product with _2Cl_2; tetra-substituted ureas,
and these and PCl_3, PCl_5, POCl_3,
COCl_2, SOCl_2 or (CO)_2Cl_2
reaction products with; and hexaalkylphosphoramide;
7. Process according to claim 1, characterized in that a catalyst selected from the group consisting of hexaalkylguanidinium salts and their hydrochloric acids is used. 8. 10^-^4~10^ for the acid group to be converted
- Characterized by using a catalyst in the range of 1 equivalent,
A method according to any one of claims 1 to 7. 9. The temperature is between 110°C and 160°C in the absence of catalyst and between 80°C and 150°C in the presence of catalyst.
Method according to any one of claims 1 to 8, characterized in that: 10. Temperature is 120°C to 160°C in the absence of catalyst
and 100°C to 13°C if a catalyst is present.
10. A method according to any one of claims 1 to 9, characterized in that the temperature is 5<0>C.